but where does it come from?
Bugs. Yes, little scaly bugs that live on prickly pear cacti in the desert. Once dried and ground up to a fine powder (I use an old coffee grinder). These little critters give off the most stunning colours from the palest, softest pinks to the deepest crimson.
I ground my bugs a few days ago, and brought them to a near-boil then left to cool for 24 hours. During which time their colour releases to create a deep crimson liquid. I strained it through a silk lined sieve and saved the ‘pulp’ to try and use again.
Cochineal will produce a variety of colours dependant on the mordant used. In this dye bath, I used Alum. I tossed in a few silk cocoons, as they make such a lovely colour reference, and will surely be used in a project one day.
Once I had the colour I was looking for, I rinsed and centrifuged the silk and let is dry.
After drying completely, I undid the resists and carefully pressed it to retain the shibori texture.
After removing this shawl from the dye bath, I experimented with different fabrics and fibres, as well as adding tartaric acid to yield more colour, resulting in varying shades. Other mordants can be used to vary the tone such as tin. An afterbath in amonia will tend toward more purple than pink. And Iron will make it more earthy, but note that the silk fibres can be damaged by iron.
If you are interested in a good reference book re: natural dyeing, try Indigo Madder and Marigold by Trudy Van Stralen.